Residential metal roofing system
http://china.toocle.com/ 2009 年 06 月 24 日 09:09 Social business
Business News Agency June 24
In today's highly competitive roofing market, a contractor to be successful in the professional and quality must go in front, for example, to correctly select the roofing systems and products. Residential metal roofing system is very good - kind of program will help to improve the status of contractors in the competition.
In recent years, residential metal roofing products in terms of applications has increased. In some areas, such as coastal and mountainous areas, the use of metal roofing system is more common than in the past. Experience shows that in the climate extremes, increasing use of metal roofing.
Metal Roofing Association (MRA) is expected, metal roofs in the residential roofing market share each year will be 20% to 25% growth rate. To achieve this goal, the metal roofing industry must continue to focus on improving the user's awareness, but also must increase efforts to roofing contractors and distributors of commercial products and their use for training. Perhaps the most fundamental is to clarify the different metal roofing products as well as the difference between these differences in a successful meet the requirements of owners of metal roofing systems in the role.
1 Application
Of residential metal roofing is a mistake to think that the majority of roofing for new construction. In fact, NRCA annual market survey, 2004, 11 percent of residential metal roofing for new, renovation of 56%, 11% for the maintenance and repair. Visible, more for the refurbishment of the metal roof, one of the reasons is that many metal roofing products can be laid on the existing roof, as well as some variety of standing seam metal tile products.
Commercially available product variety and often people will do a muddle. In North America, with over 100 vinyl tile, imitation shingles, slate and clay tile, concrete tile and other tile materials. Because each product is the exclusive production and sales, and not interoperable. To ensure correct construction and application is necessary to understand some of the products of knowledge.
2 Products
In determining the form of a metal roofing system, it is necessary to choose the roof slope and geometry of the product. For example, most of the roof tile products for the minimum slope of 3 / 12. The low sloping roof, the main use of on-site mechanical or hand joints standing seam panels, such as "double-lock" or "Three Rings" board.
Modulus products are mostly interlocking panels, ranging in size from 203 mm × 305mm to 610mm × 914 mm. This roofing system approach to a variety of thermal expansion and contraction problems. Some used in the construction or expansion of sliding clip, when the thermal expansion board "floating" up; some products are designed with the use of the board, "folding" effect, the equivalent of S-shaped plate can withstand thermal expansion and contraction of many fold. Such products can be made into imitation or imitation slate glass tile, vinyl tile, and other imitation Tongwa or flat tile.
Stiffness of these products exist in the metal plate and with the space between the grassroots so that they can be self-connected in the renovated shop in the existing roof. In fact, such systems can even through the use of wood or tile shop in a special fixation on the shingle.
In addition to the special form of modulus board, there are many products available for residential vertical seam. These products from the shop to the house along the roof, and rafters or parallel or perpendicular. Vertical seam roofing products include a variety of fixed waveforms through standing seam panels and products.
Penetrate the roof panels have a variety of standard length, laying horizontal seams and ends with the overlap can also be broken in the field size to avoid the end of the lap. The length of standing seam products are generally customized to meet the actual size of the roof.
All vertical joints in laying a key factor when products must understand that the manufacturer is required on board laid on the slats or solid board. Although these products are initially laid on the slats, but are often applied in agriculture manufacturer of solid board and asked to use the cushion.
Penetration of fixed or fixed-length standing seam roofing products, safe transportation is very important, because sometimes board up to 8 m long or even longer. To avoid such a transportation problem, sometimes the pressure-type machine can be moved into the field production. Even so, the board still need to be careful on-site transport and require specialized knowledge, because many board is shipped upright.
3 types of metal
Discussed above, a variety of metal roofing products can be made of different metals to achieve specific effects and features. MRA survey of metal roofing products with the main material is steel, there are two forms, galvanized and Galvalume.
Galvanized steel zinc plated to improve corrosion resistance, Galvalume coated steel alloy, is also for preservation purposes. Both have a variety of steel grades. Classification is based on both sides of the steel-plated zinc or aluminum coating thickness determined. Metal Construction Association, in accordance with quality standards, if the metal surface coating, then, G90 galvanized steel is the recommended minimum level, AZ50 Galvalume is the recommended minimum level. If the transparent surface finishing or coating applied when the recommended level of Galvalume AZ 55.
There are other metals can be used, such as aluminum, copper, zinc, stainless steel and tin-lead alloy. Aluminum is mainly used for the purpose of preservation and use of its malleability, can be processed into a fine wood grain tile effect of the product. The roof is always made of aluminum coated or anodized to obtain a special color and better durability. Copper, zinc and stainless steel more for no coating applications. Copper is mainly the use of its good durability and rich features aeruginous. Zinc is also used for preservation purposes as well as its malleability, low-gloss gray appearance. Stainless steel is used to obtain long-lasting, shiny silver appearance or to meet specific corrosive environment.
4 Product Compatibility
Metal roof construction, according to the electrochemical point of view, the system used in all materials must be compatible, otherwise, and even between different metals and other materials will occur between electrolysis and corrosion. This includes fixtures, flashings, gutters and adjacent wall materials, they must be compatible or avoid contact.
As mentioned above, for aesthetic, many of the metal surface has a coating or overlay. There are several coatings, including acrylic, polyester, silicone polyester, and polyvinylidene fluoride (PVDF). PVDF coatings are registered trade name of Kynar and Hvlar, they are always in shape before the coated metal roof on. More durable coating also includes color fastness and anti-powdering performance, this - point, negotiate with customers is very important.
Familiar with the coatings industry knows that the most difficult to fade the pigment is an inorganic ceramic pigments, organic pigments expensive than the use of such inorganic pigment paint pigment than good. PVDF coating used to improve viscosity of the resin coating is a fluoride, can produce a strong molecular bond will firmly grasp the paint to prevent chalking. Some modulus metal tile is applied later in forming the coating, known as "coated", will help to ensure that the process of being stretched in the shape of the metal surface to get adequate coverage. The most common type is coated stone cladding, there will be ceramic bonded to the steel surface of the stone surface. The other is applied in the molding powder coating the board, common with PVDF powder coatings. These coatings make the products with a variety of textures and colors.
Dedicated to improving the metal coating on the durability of metal roofing, steel roofing products in particular, coated with high-quality coatings to protect against climate grass-roots level, to make products with the durability of a method. In addition, metal roofing system and many other advantages.
5 Advantages
One of the advantages of metal shore side is light weight - like aluminum tile roof weighs only 4.84 kg / m2, stone cladding tile roof is 16.15kg/m2, significantly lower than other roofing materials such as fiberglass shingles is 25 .8 ~ 40 4kg/m2. As the light weight, this product can be used in the original roof, applied to reduce the weight on the roof structure.
In addition, the interlock metal roofing system features or non-interlock between the metal plate and the roof fixed and the fixed nature of most metal roofing system that has a good expose of the wind. In many cases, the product can be achieved UL 580 "Standard Roof Wind exposing test" under the UL 90 level or UL1897 "wind exposed roof covering system standards" requirement.
High wind exposing the metal roofing is the place to be given priority in many a reason, but in some places the use of the system is to use its fire resistance. In fact, the last 1960s and 1970s in the United States some of the favorite places with shingles, vinyl tile on the use of aluminum and steel roofing products as fire. Over the past few decades the use of various types of metal roofing is a lot out of this consideration.
2003 International Building Code requirements for fire performance of roofing systems should be tested, but does not include steel and copper tile (board) roof, taking into account their inherent good fire performance. Of course, the metal roof during the pre-construction best check what the local building codes.
Another advantage of the metal system is above the coating allows it to be "cool" roofing system. Metal roof coating on the surface will not be set because of its smooth gray, more often than in the porous or rough coating on the surface of roofing materials can be longer and the light color to keep clean. Owners from time to time with clean water rinse. In addition, for most of the coating on the metal roof with high radiation, according to the different coatings, the radiation rate of 0.75 minimum, maximum up to 0.95, so the roof to absorb heat quickly release back to the atmosphere.
As technology advances, many metal roofing products with a coating of infrared reflecting pigments to add these specially treated pigments, even in dark colors can also have very high solar reflective performance. For example, non-reflective surface of the metal coating of dark brown total solar reflectance of only 6% to 8%, reflecting pigments added, the total solar reflectance can be increased to 25% to 30% or even higher. This meets the government agencies and public sector of the "cold" roof reflectivity requirements of the initial value.
In addition, the metal roof system design and cushion between the metal roof or metal and the air space between the stationary set, heat conduction through the suspension to further improve energy efficiency. Florida Solar Energy Center in accordance with the test, and the use of traditional roofing materials, many of the traditional metal tile roof in imitation of the still air of the attic space so that the heat is reduced by 30% or more of a factor. For laying the battens on the modulus of the product, and standing seam metal roofing products, it is still possible through a ventilation space to further improve energy efficiency.
Another advantage of metal products in the recycled material content. Most steel used in metal roofing with 25% to 35% recycled materials. Non-ferrous metals such as aluminum, copper, recycled material content of up to 95%.
Metal roofing is a major environmental factor in the sustainability of its excellent durability reduces the future consumption of raw materials. The life of metal roofing system and related products used. Uncoated steel roofing can last 20 to 30 years, plus a longer coating life. Have a coating or to the original stone cladding of the roof systems often guarantee period of up to 30 to 50 years, and re-applied coating life can be extended. Life even after the arrival of metal roofing can also be 100% recycling.
Most metal roofing easy to bend, to adapt to the unconventional form of roof design, including circular, oval and with a convex curve of the roof. For standing seam metal roofing system, many manufacturers offer matching wedge, narrow bottom width to accommodate the circular roof top needs, as well as curved concave or convex panels for the rafters.
Other hand, the modulus of the metal roofing panels have different ways to adapt to the special roof. Many tile cross-section is curved, for a round roof. In addition, 381 mm or less exposed some of the module board is very easy for most of the roof curve. Of course, the most fundamental thing is to get the manufacturer's information and help to decide how to live doing the best.
6 Annex
Although some form of special needs of custom sheet metal roofing and flashing, but residential metal roofing manufacturers to provide a wide range of standardized accessories available for the eaves, gables, roof drains, roof and wall slope changes and roof junction . In some cases, the manufacturer may also provide on-site production of attachments drawings. Many residential roof detail, including the rain dripping from the roof oriented along the tank.
On the standing seam roof system, the bottom edge of each piece of board or drip edge pieces around the starting roll. Standing seam roof panels with a clip and grip, and then secure the upper plate. For the vertical plate through a fixed and certain parts can not be locked into the starting tile-shaped plate, the manufacturer will usually provide sealing of the roof and finally fixed with detailed steps.
There are several methods of disposal gable, usually depends on roof shape. Roof gutters are three basic forms, used in conjunction with a variety of metal roofing: flat discoid drains, l or 2 drain pan so that the roof water and drain (open valley).
The disposal of the roof there are several methods. Most vertical plate with long roof and ridge cap - as long 3 m or 4 m.
Wall, roof slope changes and the transfer of processing often requires on-site production of the pan of water to meet the roof shape. Manufacturers recommend some form of pan-water, in the small bending machine or metal working shop in the local production. Skylights and chimneys often need a special pan of water, some well-known brand manufacturers provide supporting pan of water.
For skylights and chimneys important to remember that should not be overly dependent on sealant. Although the need for the appearance of the sealant, waterproofing can be used as auxiliary means, but any metal roof system flashings the first line of defense should be a pan of water itself. Sealant and the cushion is just an additional waterproofing measures.
Skylight in the roof should be done on the circle, so that the roof height was significantly higher than the metal plate. Whenever possible, the chimney at the pan of water should be embedded in masonry structure. Roof wall junction should be inserted or pan of water out into the wall up.
Attic ventilation and plumbing requirements shall be the manufacturer's construction. Metal roofing system designed specifically for the Pan-there are many kinds of water, sometimes even the color can be very well equipped.
Of course, experienced roofing contractor knows, when you think you have met all of the roof when a new issue again. It should be remembered, flashing the basic principle is to design the water is always in the top surface of the plate movement. Good design often pan of water under the roof auxiliary water channel, in order to increase water reliability. Another point is not to make the roof of garbage, leaves, snow and ice blocking the water path. In addition, the design of special flashings should consult the manufacturer or to the roof construction metal roof reference NRCA Manual (The NRCA Architectural SheetMetal and MetalRoofine Manu al).
7 Ventilation
Roof ventilation manufacturers recommended practices, which may include proprietary products and markets for sale of roof ventilation products. Many vertical slit through the use of ventilation products, closed with a specially made so that air can flow between the ribs on the roof, eaves care pull air as the air inlet.
Many people have a wrong perception that metal roofing systems need to increase attic ventilation. In fact, no matter what kind of attic ventilation is critical in roofing materials, metal, and use of the system have not the slightest change. In the choice of roof ventilation should also be considered when. Must remember that the amount of condensation generated warm air and cold as the result of surface contact. Attic ventilation is designed to eliminate the chance of condensation.
8 Construction
Residential metal roofing system to be set up cushion on the grounds that: the system in the roof structure during construction to keep dry; an additional waterproofing means; make condensation occurred in the plate on the back, to avoid the damp grass roots roof.
Although, 30 years shingle roofing mat is a standard option, but now contractors have turned to the synthesis of new lighter materials, so that each volume covers the area more. Of course, there are requirements specification, can also use self-adhesive cushion. The surface of these products are smooth, without granules and thus will not damage the metal plate on the back.
Also, in most of the metal to be careful walking on the roof. Roofing contractor to the owner shows how to walk on the safer, better able to leave a written guide. Walking on the steep roof, no matter what material is a challenge, metal roofing is no exception. In many cases, the fixed ladder on the roof, then support and ladder access aisle board composition.
Most manufacturers offer various forms of construction training.
In the past, metal roofing for residential purposes, property owners and contractors, lack of training, lack of awareness is a major obstacle to the promotion of this roof, and now the situation has greatly improved.